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      miscellaneous
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<h1>Misc Tools</h1>

The misc package has various tools for splitting/merging indices,
changing norms, finding high freq terms, and others.

<a id="DirectIODirectory"></a>
<h2>DirectIODirectory</h2>

<p>
{@link org.apache.lucene.misc.store.DirectIODirectory} is a Directory implementation that bypasses the
OS's buffer cache (using direct IO) for any IndexInput and IndexOutput
used during merging of segments larger than a specified size (default
10 MB).  This avoids evicting hot pages that are still in-use for
searching, keeping search more responsive while large merges run.

<p>
See <a target="_top" href="http://blog.mikemccandless.com/2010/06/lucene-and-fadvisemadvise.html">this blog post</a>
for details.

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